Sofa



FIG. 1 is a perspective view of a sofa according to my new design;

FIG. 2 is a front elevation view thereof;

FIG. 3 is a top plan view thereof;

FIG. 4 is a rear elevation view;

FIG. 5 is a bottom plan view; and,

FIG. 6 is a side elevation view, the opposite side being substantially a mirror image thereof. 

The ornamental design for a sofa, as shown and described. 